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    <meta charset="UTF-8">
    <title>变量的注意点</title>
    <script type="text/javascript">
        var var_01=1;
        console.log(var_01);
        var var_01=2;
        console.log(var_01);
        var_01=3;
        console.log(var_01);
        var var_03;
        console.log(var_03)
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